In this case report we describe a short circuit in the Riata 1570 defibrillator lead (Riata 1570, St. Jude Medical, St. Paul, MN, USA) that was unsuspected owing to normal lead parameters until defibrillator threshold testing at the time of elective generator change. On this occasion, the short circuit manifested as unsuccessful defibrillation of ventricular fibrillation with immediate battery depletion. This report adds weight to existing concerns over narrow caliber leads, it draws attention to the possibility of lead malfunction despite unremarkable interrogation, and lastly it highlights the potential role of routine defibrillator threshold testing, particularly at elective generator change (an issue that remains sparingly addressed in the existing literature).

©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.